JP3287215B2 - Manufacturing method of nickel positive plate for alkaline storage battery - Google Patents

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、ニッケル−カドミ
ウム蓄電池等に用いられるニッケル正極板の改良に関す
るものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a nickel positive electrode plate used for a nickel-cadmium storage battery or the like.

【０００２】[0002]

【従来の技術】アルカリ蓄電池用ニッケル正極の製造法
としては、従来より主にニッケル塩を微孔内に含浸した
多孔性基板をアルカリ溶液中で陰電解する方法、あるい
は陰電解せずにアルカリ溶液中で水酸化ニッケルに転換
処理を行う化学含浸法、熱分解法、電解析出法などが知
られている。2. Description of the Related Art Conventionally, a method for producing a nickel positive electrode for an alkaline storage battery has mainly been a method in which a porous substrate impregnated with nickel salts in micropores is subjected to negative electrolysis in an alkaline solution, or an alkaline solution without negative electrolysis. A chemical impregnation method, a thermal decomposition method, an electrolytic deposition method, and the like, in which nickel hydroxide is converted into nickel hydroxide, are known.

【０００３】電池の用途拡大につれて小型化、高性能化
が要求されるようになり、消費熱エネルギー、電力が少
なく、活物質利用率が高く、高容量密度のニッケル正極
板を低コストで製造する方法が待望されてきている。そ
こで、必要とする水酸化ニッケルの過半量を電解析出法
によって充填し、これに引き続いて化学含浸法により、
残りの水酸化ニッケルを充填することによって高容量密
度で、なおかつ活物質利用率も高い水酸化ニッケル正極
を低コストで得る方法が提案されている（特公平２−４
１８６５号公報）。As the use of batteries has been expanded, miniaturization and higher performance have been required, and heat-consumption energy, less power, high utilization of active materials, and high-capacity density nickel positive plates are manufactured at low cost. There is a long-awaited method. Therefore, the majority of the required nickel hydroxide is filled by the electrolytic deposition method, and subsequently, by the chemical impregnation method,
A method has been proposed in which a nickel hydroxide positive electrode having a high capacity density and a high active material utilization rate is obtained at a low cost by filling the remaining nickel hydroxide.
No. 1865).

【０００４】また、アルカリ蓄電池を電源に用いる機器
の小型化につれて、電源としてより小さく、高容量密度
の電池が要望されていた。そこで、化学含浸法によって
得た水酸化ニッケルを主成分とする２つの層の間にサン
ドイッチ構造的に水酸化コバルトあるいはコバルト酸化
物を主成分とする層を形成することにより、活物質の利
用率、電池としての放電電位特性を向上させるという方
法も提案されている（特公平６−７７４５２号公報）。[0004] Further, with the miniaturization of equipment using an alkaline storage battery as a power supply, there has been a demand for a smaller and higher capacity density battery as a power supply. Therefore, by forming a layer mainly composed of cobalt hydroxide or cobalt oxide in a sandwich structure between two layers mainly composed of nickel hydroxide obtained by the chemical impregnation method, the utilization rate of the active material is improved. A method of improving the discharge potential characteristics of a battery has also been proposed (Japanese Patent Publication No. 6-77452).

【０００５】このようなニッケル正極を用いたニッケル
−カドミウム蓄電池やニッケル−水素蓄電池は、室温下
で適宜の電流値で充放電する、サイクル用途で使用して
いる限りは、電解析出法と化学含浸法により、それぞれ
水酸化ニッケルを一定重量比率ずつ充填したニッケル正
極板でも何ら問題なくその機能を発揮してきた。[0005] Nickel-cadmium storage batteries and nickel-hydrogen storage batteries using such a nickel positive electrode charge and discharge at an appropriate current value at room temperature. Even with a nickel positive electrode plate filled with nickel hydroxide at a constant weight ratio by the impregnation method, its function has been exhibited without any problem.

【０００６】[0006]

【発明が解決しようとする課題】ところが最近では電池
用途の広がりや機器の小型化などが進み、例えば太陽電
池の起電力を貯える蓄電用バックアップ電池や、屋外に
設置された機器の駆動用電池等においては、単なる高容
量化だけでなく、長期間にわたる高信頼性、つまり長寿
命化が要求されるようになってきた。そこで、上記の電
池を高温下でＪＩＳ Ｃ ８７０５の７，３，９に規定
されている耐久特性試験を行ってみたところ、正極側の
導電性が低下していることがわかった。この導電性の低
下により、正極側の分極が大きくなり、早期に電池の容
量低下に至っていた。Recently, however, the use of batteries and the miniaturization of equipment have been advanced, and for example, backup batteries for storage of electromotive force of solar cells, and batteries for driving equipment installed outdoors have been developed. , Not only high capacity but also high reliability for a long time, that is, long life has been required. Then, when the durability test specified in JIS C 8705 7, 3, 9 was performed on the above battery at a high temperature, it was found that the conductivity on the positive electrode side was reduced. Due to this decrease in conductivity, the polarization on the positive electrode side increased, leading to an early decrease in battery capacity.

【０００７】また、水酸化ニッケルを主成分とする２つ
の層の間にサンドイッチ構造的に水酸化コバルトあるい
はコバルト酸化物を主成分とする層を形成する方法にし
ても、２つの層を形成する水酸化ニッケルの製造法が化
学含浸法であり、製法上から基板の微孔内への活物質充
填量は制限されて高容量密度の極板が得難く、また充填
した活物質も粒径的に大きく、その利用率が電解析出法
で得られる水酸化ニッケルと比較して低いという問題点
があり、長期間にわたって導電性を確保し、放電容量を
一定値以上に保つのは難しかった。[0007] Further, even in a method of forming a layer mainly containing cobalt hydroxide or cobalt oxide in a sandwich structure between two layers mainly containing nickel hydroxide, the two layers are formed. The method of producing nickel hydroxide is a chemical impregnation method, which limits the amount of active material filling the micropores of the substrate from the manufacturing method, making it difficult to obtain a high capacity density electrode plate. However, it has a problem that its utilization factor is lower than that of nickel hydroxide obtained by the electrolytic deposition method, and it has been difficult to secure conductivity for a long period of time and keep the discharge capacity at a certain value or more.

【０００８】[0008]

【課題を解決するための手段】上記課題を解決するため
に本発明は、例えばパンチングメタルなどの芯材に塗着
するペースト中にコバルトを添加し、焼結を行った焼結
ニッケル基板などの多孔性金属基板に活物質をなす水酸
化ニッケルの一部を電解析出法によって充填し、ついで
コバルト酸化物層を化学含浸法により形成し、その後前
記必要とする総量の過半量の水酸化ニッケルを硝酸ニッ
ケルと硝酸コバルトの混合溶液により化学含浸法で充填
するものである。SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a sintered nickel substrate or the like obtained by adding cobalt to a paste applied to a core material such as a punching metal and performing sintering. The porous metal substrate is filled with a part of nickel hydroxide as an active material by an electrolytic deposition method, and then a cobalt oxide layer is formed by a chemical impregnation method. Is filled with a mixed solution of nickel nitrate and cobalt nitrate by a chemical impregnation method.

【０００９】この際の水酸化ニッケルの充填量は、電解
析出法で得られたそれが必要活物質総量の約３０重量
％、化学含浸法で得られたそれが必要活物質量の約７０
重量％であることが好ましい。In this case, the amount of nickel hydroxide charged is about 30% by weight of the total amount of the required active material obtained by the electrolytic deposition method, and about 70% of the required amount of the active material obtained by the chemical impregnation method.
% By weight.

【００１０】[0010]

【発明の実施の形態】本発明の請求項１に記載の発明
は、パチングメタルなどの芯材に塗着するペースト中に
酸化コバルトなどのコバルト酸化物を添加し、焼結を行
い、焼結ニッケル基板を作製し、電解析出法により必要
とする水酸化ニッケルの一部を充填し、ついでコバルト
酸化物層を化学含浸法により形成させ、その後に化学含
浸法により前記必要総量のうちの過半量の水酸化ニッケ
ルを硝酸ニッケルと硝酸コバルトの混合溶液により充填
するものであり、基板の微孔内に密着し粒径的に小さい
電解析出法によって得られた水酸化ニッケルは量的、厚
み的に少なく、化学含浸法によって得られた水酸化ニッ
ケルは、電解析出法によるそれよりも粒径的に大きく、
量的、厚み的にも大であることから極板内部での電解液
の移動、拡散が良好にでき、電解液量が少なく極板内奥
部の充填活物質まで長期間にわたり電解液が到達しにく
いという課題を解決でき、芯材と活物質、及び活物質と
活物質の導電性ネットワークの向上や電解析出で得られ
る水酸化ニッケルを一部充填することにより、その高い
充填密度を利用して高容量密度で、活物質量の利用率が
高く、しかも高温下においても長寿命化が図れるニッケ
ル正極板とすることができる。BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is characterized in that a cobalt oxide such as cobalt oxide is added to a paste to be applied to a core material such as a patting metal, and sintering is performed. A substrate is prepared, a part of nickel hydroxide required by an electrolytic deposition method is filled, then a cobalt oxide layer is formed by a chemical impregnation method, and then a majority of the required total amount is formed by a chemical impregnation method. Of nickel hydroxide is filled with a mixed solution of nickel nitrate and cobalt nitrate. The nickel hydroxide obtained by the chemical impregnation method is larger in particle size than that by the electrolytic deposition method,
Because of its large volume and thickness, the electrolyte can be moved and diffused well inside the electrode plate, and the amount of electrolyte is small and the electrolyte can reach the filled active material deep inside the electrode plate for a long time It is possible to solve the problem that it is difficult to solve the problem and use the high packing density by partially filling the core material and the active material, and improving the conductive network of the active material and the active material, and partially filling nickel hydroxide obtained by electrolytic deposition. As a result, a nickel positive electrode plate having a high capacity density, a high utilization rate of the amount of active material, and a long life at high temperatures can be obtained.

【００１１】[0011]

【実施例】次に、本発明の具体例を説明する。ニッケル
粉末と酸化コバルト粉末を重量比で９０：１０の割合で
混合し、メチルセルロースのエチレングリコール溶液で
十分練合しペースト状にした物を開孔鋼板に塗着乾燥
し、１０００℃で焼結を行い、多孔度８０％の焼結ニッ
ケル基板を作製した。この基板を用いて、電解析出法に
おける電解液として、濃度３．５モル／ｌ，ｐＨ２．０
の硝酸ニッケル溶液を用い、その液温度を８０℃として
浸漬し、これを陰極として電解析出を行った。なお電解
析出による硝酸ニッケルの充填量は、アルカリ水溶液に
よる転換後の水酸化ニッケル換算で必要総量の約３０重
量％とした。この後、充填基板の乾燥を行い、引き続い
て、この基板を濃度３．０モル／ｌ，ｐＨ１．５、液温
度８０℃の硝酸コバルト水溶液中に浸漬し、硝酸コバル
トの含浸を行った後に、乾燥を施し、濃度４．０モル／
ｌ、液温度６０℃のか性ソーダ水溶液中に浸漬し、引き
続いて水洗処理を行った。その後、濃度３．０モル／ｌ
の硝酸ニッケルと、濃度０．０５モル／ｌの硝酸コバル
トとの混合液水溶液を用い、液温度を８０℃としてこれ
に浸漬した後に、乾燥を行い、濃度４．０モル／ｌ、液
温度６０℃のか性ソーダ水溶液中に浸漬し、硝酸ニッケ
ル、硝酸コバルトをそれぞれ水酸化ニッケル、水酸化コ
バルトに転換した後に水洗処理を行った。さらにこのニ
ッケル塩およびコバルト塩の化学含浸、アルカリ浸漬、
水洗の一連の工程を複数回くり返して必要総量の約７０
重量％の水酸化ニッケルを充填した。この活物質充填後
の基板を３５×１５０ｍｍに裁断し、本発明の実施例に
よるニッケル正極板ａを作製した。この正極板を用い公
知のカドミウム負極と組み合わせて、公称容量７００ｍ
ＡｈのＡサイズの密閉型ニッケル−カドミウム蓄電池Ａ
を作製した。比較例として、上記実施例と同様にコバル
トを添加したニッケル焼結基板用いて、電解析出法によ
り必要総量の７０重量％相当の水酸化ニッケルの充填を
行った後、硝酸ニッケルと硝酸コバルトとの混合溶液に
浸漬し、残りの３０重量％相当の水酸化ニッケルを充填
して作製した正極板を比較例によるニッケル正極板ｂと
し、実施例同様にＡサイズの密閉型ニッケル−カドミウ
ム蓄電池を作製し、比較例による電池Ｂを得た。また、
化学含浸法により総活物質量の約６０重量％を充填した
後、硝酸コバルトの含浸を行い、残りの約４０重量％の
水酸化ニッケルをやはり化学含浸法によりコバルトを添
加した焼結基板に充填した極板を比較例ｃとし、これを
用いて実施例同様に密閉型ニッケル−カドミウム蓄電池
を構成し、比較例による電池Ｃを得た。そして、ニッケ
ル粉末のみをメチルセルロースのエチレングリコール溶
液と混練し、ペースト状にし開孔鋼板に塗着、乾燥、焼
結の一連の工程を行いニッケル焼結基板を作製し、上記
実施例と同様に電解析出法により必要総量の約３０重量
％相当の水酸化ニッケルの充填を行った後、硝酸コバル
トの含浸を行い、残りの約７０重量％の水酸化ニッケル
を硝酸ニッケルと硝酸コバルトの混合溶液に浸漬し、充
填して作製した正極板を比較例によるニッケル正極板ｄ
とし、比較例による電池Ｄを得た。また、電解析出法に
より必要活物質量の７０重量％、化学含浸法により必要
活物質量の３０重量％として充填し、その他の条件につ
いては実施例と同様にして極板の作製を行ったニッケル
正極板をｅとし、比較例による電池Ｅを得た。そして、
硝酸コバルト溶液の化学含浸まで実施例と同様にして行
い、残りの約７０重量％の水酸化ニッケルの充填を濃度
３．０モル／ｌの硝酸ニッケル水溶液を用い、液温度８
０℃としてこれに浸漬した後に、乾燥を行い、濃度４．
０モル／ｌ、液温度６０℃のか性ソーダ水溶液中に浸漬
し、硝酸ニッケルをそれぞれ水酸化ニッケルに転換した
後に水洗処理を行った。さらにこのニッケル塩の化学含
浸、アルカリ浸漬、水洗の一連の工程を複数回くり返し
て必要総量の約７０重量％の水酸化ニッケルを充填した
極板を比較例ｆとし、比較例による電池Ｆを得た。Next, specific examples of the present invention will be described. A nickel powder and a cobalt oxide powder are mixed at a weight ratio of 90:10, kneaded sufficiently with an ethylene glycol solution of methylcellulose, and a paste is applied to a perforated steel sheet and dried. Then, a sintered nickel substrate having a porosity of 80% was produced. Using this substrate, as an electrolytic solution in the electrolytic deposition method, a concentration of 3.5 mol / l and a pH of 2.0
Of nickel nitrate solution, and immersion was performed at a solution temperature of 80 ° C., and electrolytic deposition was performed using this as a cathode. The filling amount of nickel nitrate by electrolytic deposition was about 30% by weight of the required total amount in terms of nickel hydroxide after conversion with an aqueous alkali solution. Thereafter, the filled substrate is dried. Subsequently, the substrate is immersed in an aqueous solution of cobalt nitrate having a concentration of 3.0 mol / l, pH 1.5, and a liquid temperature of 80 ° C., and impregnated with cobalt nitrate. After drying, a concentration of 4.0 mol /
1, immersed in an aqueous solution of caustic soda at a liquid temperature of 60 ° C., and subsequently washed with water. Thereafter, the concentration is 3.0 mol / l.
Of a mixed solution of nickel nitrate and cobalt nitrate having a concentration of 0.05 mol / l was immersed in the mixture at a liquid temperature of 80 ° C., and then dried to obtain a concentration of 4.0 mol / l and a liquid temperature of 60 mol / l. It was immersed in an aqueous solution of caustic soda at ℃ to convert nickel nitrate and cobalt nitrate into nickel hydroxide and cobalt hydroxide, respectively, and then washed with water. Furthermore, chemical impregnation of this nickel salt and cobalt salt, alkali immersion,
Repeat the series of washing steps several times to reduce the total
Weight percent nickel hydroxide was charged. The substrate after the filling of the active material was cut into a size of 35 × 150 mm to produce a nickel positive electrode plate a according to the embodiment of the present invention. Using this positive electrode plate in combination with a known cadmium negative electrode, a nominal capacity of 700 m
Ah size A sealed nickel-cadmium storage battery A
Was prepared. As a comparative example, a nickel-sintered substrate to which cobalt was added in the same manner as in the above example was used, and nickel hydroxide equivalent to a required total amount of 70% by weight was filled by an electrolytic deposition method. A positive electrode plate prepared by immersion in a mixed solution of (1) and filling with the remaining 30% by weight of nickel hydroxide was used as a nickel positive electrode plate b according to a comparative example, and an A-size sealed nickel-cadmium storage battery was prepared in the same manner as in the example. Then, a battery B according to a comparative example was obtained. Also,
After filling about 60% by weight of the total active material amount by the chemical impregnation method, impregnation with cobalt nitrate is performed, and the remaining about 40% by weight of nickel hydroxide is also filled into the sintered substrate to which cobalt is added by the chemical impregnation method. The sealed electrode plate was used as a comparative example c, and a sealed nickel-cadmium storage battery was formed in the same manner as in the example, thereby obtaining a battery C according to the comparative example. Then, only the nickel powder was kneaded with an ethylene glycol solution of methylcellulose to form a paste, which was then applied to a perforated steel plate, dried, and sintered to produce a nickel sintered substrate. After filling nickel hydroxide equivalent to about 30% by weight of the required total amount by the analysis method, impregnation with cobalt nitrate is performed, and the remaining about 70% by weight of nickel hydroxide is added to a mixed solution of nickel nitrate and cobalt nitrate. The positive electrode plate prepared by immersion and filling was used as a nickel positive electrode plate d according to a comparative example.
The battery D according to the comparative example was obtained. Further, the electrode plate was filled by 70% by weight of the required amount of the active material by the electrolytic deposition method, and 30% by weight of the required amount of the active material by the chemical impregnation method. Using the nickel positive electrode plate as e, a battery E according to a comparative example was obtained. And
The chemical impregnation of the cobalt nitrate solution was carried out in the same manner as in the example, and the remaining 70% by weight of nickel hydroxide was filled with a 3.0 mol / l nickel nitrate aqueous solution at a liquid temperature of 8%.
After immersion in this at 0 ° C., drying was carried out and the concentration was 4.
It was immersed in an aqueous solution of caustic soda at 0 mol / l and a liquid temperature of 60 ° C., and after converting nickel nitrate to nickel hydroxide, a water washing treatment was performed. Further, a series of steps of chemical impregnation of this nickel salt, alkali immersion, and washing with water was repeated a plurality of times, and an electrode plate filled with about 70% by weight of nickel hydroxide of a required total amount was designated as Comparative Example f, and a battery F according to Comparative Example was obtained. Was.

【００１２】これらＡ，Ｂ，Ｃ，Ｄ，Ｅ，Ｆの各電池の
活物質充填密度と２０℃の一定温度で０．１Ｃで１５時
間充電し、０．２Ｃで終止電圧１．０Ｖまで放電するサ
イクルを１サイクルとしたモードで充放電して、２サイ
クル目の放電容量により電池特性を評価した。その結果
を（表１）に示す。Each of the batteries A, B, C, D, E and F was charged at a constant temperature of 20 ° C. and at a constant temperature of 20 ° C. for 15 hours at 0.1 C, and discharged at 0.2 C to a final voltage of 1.0 V. The charging and discharging were performed in a mode in which one cycle was performed, and the battery characteristics were evaluated based on the discharge capacity in the second cycle. The results are shown in (Table 1).

【００１３】[0013]

【表１】 [Table 1]

【００１４】（表１）から明らかなように、コバルト酸
化物の層を電解析出法で得られる水酸化ニッケルと化学
含浸法で得られる水酸化ニッケルとの間に形成させた電
池Ａは、コバルト酸化物の層がない比較例の電池Ｂより
も活物質の利用率が高い。これは、コバルト酸化物は電
解析出法で得られる水酸化ニッケルと化学含浸で得られ
る水酸化ニッケルの周りにコバルト酸イオンとして拡散
してゆき、充電時に導電性が良好なオキシ水酸化コバル
トになって、活物質の利用率が向上していると考えられ
る。また、化学含浸法で得られる水酸化ニッケルの層
間、粒子間にコバルト酸化物を形成させた比較例電池Ｃ
よりも、電池Ａは高容量密度で、活物質利用率も高い。
これは、化学含浸法で得られる水酸化ニッケルと比較し
て、電解析出法で得られる水酸化ニッケルの接触面積が
大きく、水酸化ニッケル粒子の表面部分にコバルト酸化
物層を形成させる効果が大きくなるためと考えられる。
また、基板中にコバルトを含有していない比較例の電池
Ｄ、及び化学含浸での水酸化ニッケルの充填において、
硝酸コバルトとの混合液でない比較例の電池Ｆよりも活
物質利用率が高い。これは、基板中にコバルト、及び化
学含浸法で含浸を行った水酸化ニッケルとともに水酸化
コバルトが存在することにより、基板と電解析出法で充
填を行った水酸化ニッケル、電解析出法で充填した水酸
化ニッケルと化学含浸法で充填した水酸化ニッケル、化
学含浸法で充填した水酸化ニッケル同士の導電性が相乗
効果的に向上しているためと考えられる。As apparent from Table 1, the battery A in which the cobalt oxide layer was formed between the nickel hydroxide obtained by the electrolytic deposition method and the nickel hydroxide obtained by the chemical impregnation method, The utilization rate of the active material is higher than that of the battery B of the comparative example without the cobalt oxide layer. This is because cobalt oxide diffuses around the nickel hydroxide obtained by the electrolytic deposition method and the nickel hydroxide obtained by the chemical impregnation as cobalt oxide ions, and forms a cobalt oxyhydroxide having good conductivity during charging. It is considered that the utilization rate of the active material has improved. Comparative battery C in which cobalt oxide was formed between layers and between particles of nickel hydroxide obtained by a chemical impregnation method.
Battery A has a higher capacity density and a higher active material utilization rate than that of battery A.
This is because the contact area of the nickel hydroxide obtained by the electrolytic deposition method is larger than that of the nickel hydroxide obtained by the chemical impregnation method, and the effect of forming a cobalt oxide layer on the surface of the nickel hydroxide particles is improved. It is thought that it becomes big.
Further, in the battery D of the comparative example containing no cobalt in the substrate, and in the filling of nickel hydroxide by chemical impregnation,
The active material utilization is higher than that of the battery F of the comparative example which is not a mixed solution with cobalt nitrate. This is due to the presence of cobalt hydroxide in the substrate, together with cobalt hydroxide and nickel hydroxide impregnated by the chemical impregnation method. This is probably because the conductivity between the filled nickel hydroxide, the nickel hydroxide filled by the chemical impregnation method, and the nickel hydroxide filled by the chemical impregnation method is synergistically improved.

【００１５】また、電池Ａ，Ｂ，Ｃ，Ｄ，Ｅ，ＦのＪＩ
Ｓ Ｃ ８７０５の７，３，９に規定されているサイク
ルの耐久特性評価を行った。図１に雰囲気温度５０℃で
のサイクル数と１サイクル目の容量を１００としたとき
の各サイクルの容量比率（標準容量比率）との関係を示
す。極板中における導電性が高い電池Ａは長期間にわた
って特性が良好である。しかし、電池Ｂでは電解析出と
化学含浸で充填した水酸化ニッケル相互間での導電性が
不十分なために早いサイクルで特性劣化が起こってい
る。また、電池Ｃにおいてもある程度の導電性は確保さ
れているが、不十分であり、特性劣化が起こっている。
電池Ｄ，Ｆにおいても導電性はかなり確保されている
が、長期にわたり特性を維持するための導電性という面
では不十分である。電池Ｅにおいては、活物質利用率は
ほぼ同等であるが、５０℃のサイクル試験を行うと電解
液が極板内奥部の細孔まで拡散が良好な電池Ａに劣る。
なお、本実施例ではニッケルとコバルトの塩として硝酸
塩を用いたが、硫酸塩を用いた場合においてもほぼ同様
の効果が得られることはいうまでもない。The batteries A, B, C, D, E, and F
The durability characteristics of the cycle specified in 7, 8 and 7 of SC8705 were evaluated. FIG. 1 shows the relationship between the number of cycles at an ambient temperature of 50 ° C. and the capacity ratio of each cycle (standard capacity ratio) when the capacity of the first cycle is 100. Battery A having high conductivity in the electrode plate has good characteristics over a long period of time. However, in battery B, the characteristics deteriorated in an early cycle due to insufficient conductivity between nickel hydroxide filled by electrolytic deposition and chemical impregnation. Further, the battery C also has a certain degree of conductivity, but is insufficient, and the characteristics are deteriorated.
Batteries D and F also have considerable conductivity, but are insufficient in terms of conductivity for maintaining characteristics over a long period of time. In the battery E, the utilization rate of the active material is almost the same.
In this embodiment, nitrate is used as the salt of nickel and cobalt. However, it is needless to say that substantially the same effect can be obtained when sulfate is used.

【００１６】[0016]

【発明の効果】以上のように、本発明では多孔性金属基
板中にコバルトを含有させ、電解析出法で得られる水酸
化ニッケルを必要とする活物質総量の一部として充填し
た後に、コバルト酸化物層を化学含浸で形成させ、つい
で必要とする総量のうち過半量の水酸化ニッケルを化学
含浸法により硝酸ニッケルと硝酸コバルトの混合溶液に
より充填し、基板−基板中のコバルト−電解析出法によ
る水酸化ニッケル−化学含浸による水酸化コバルト−化
学含浸による水酸化ニッケル−化学含浸による水酸化コ
バルト−化学含浸による水酸化ニッケルという模式的に
はサンドイッチ構造にし、導電性を相乗効果的に向上さ
せ、さらに極板内奥部までの電解液の拡散を良好にした
ことにより高容量密度で、活物質の利用率が高く、長寿
命なニッケル正極板を得ることができる。As described above, according to the present invention, cobalt is contained in the porous metal substrate, and nickel hydroxide obtained by the electrolytic deposition method is filled as a part of the total amount of the necessary active material. An oxide layer is formed by chemical impregnation, and then a majority of the required amount of nickel hydroxide is filled with a mixed solution of nickel nitrate and cobalt nitrate by a chemical impregnation method. Nickel hydroxide by chemical method-Cobalt hydroxide by chemical impregnation-Nickel hydroxide by chemical impregnation-Cobalt hydroxide by chemical impregnation-Nickel hydroxide by chemical impregnation And the diffusion of the electrolyte into the inner part of the electrode plate is improved, so that the nickel positive electrode has a high capacity density, a high utilization rate of the active material, and a long life. It is possible to obtain.

【図面の簡単な説明】[Brief description of the drawings]

【図１】実施例における電池のサイクル数と１サイクル
目の容量を１００としたときの各サイクルでの標準容量
比率との関係を示す図FIG. 1 is a diagram showing a relationship between the number of cycles of a battery and a standard capacity ratio in each cycle when the capacity of the first cycle is set to 100 in the embodiment.

フロントページの続き (56)参考文献 特開 昭59−27457（ＪＰ，Ａ) 特開 平９−274914（ＪＰ，Ａ) 特開 平９−274916（ＪＰ，Ａ) 特公 平２−41865（ＪＰ，Ｂ２) 特公 平６−77452（ＪＰ，Ｂ２) (58)調査した分野(Int.Cl.⁷，ＤＢ名) H01M 4/26 H01M 4/32 Continuation of the front page (56) References JP-A-59-27457 (JP, A) JP-A-9-274914 (JP, A) JP-A-9-274916 (JP, A) JP 2-41865 (JP) , B2) Tokiko Hei 6-77452 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) H01M 4/26 H01M 4/32

Claims (3)

(57)【特許請求の範囲】(57) [Claims] 【請求項１】多孔性金属基板中にコバルトを含有し、さ
らに基板の孔内に活物質をなす水酸化ニッケルを電解析
出法によって必要活物質量の一部として充填し、ついで
コバルト酸化物層を化学含浸法により形成し、その後、
前記の必要とする総量のうち過半量の水酸化ニッケルを
化学含浸法によって充填することを特徴とするアルカリ
蓄電池用ニッケル正極板の製造法。A porous metal substrate contains cobalt, and nickel hydroxide serving as an active material is filled in a hole of the substrate as a part of a necessary amount of the active material by an electrolytic deposition method. Forming a layer by chemical impregnation, then
A method for producing a nickel positive electrode plate for an alkaline storage battery, comprising filling a majority amount of nickel hydroxide in the required total amount by a chemical impregnation method. 【請求項２】電解析出法によって得られた水酸化ニッケ
ルの充填量が必要活物質総量の約３０重量％であり、化
学含浸法によって得られた水酸化ニッケルの充填量が前
記必要活物質量の約７０重量％である請求項１記載のア
ルカリ蓄電池用ニッケル正極板の製造法。2. The amount of nickel hydroxide obtained by the electrolytic deposition method is about 30% by weight of the total amount of the required active material, and the amount of nickel hydroxide obtained by the chemical impregnation method is the amount of the required active material. The method for producing a nickel positive electrode plate for an alkaline storage battery according to claim 1, which is about 70% by weight of the amount. 【請求項３】水酸化ニッケルを充填する化学含浸法での
塩溶液として、硝酸ニッケルと硝酸コバルトとの混合溶
液を用いた請求項１記載のアルカリ蓄電池用ニッケル正
極板の製造法。3. The method for producing a nickel positive electrode plate for an alkaline storage battery according to claim 1, wherein a mixed solution of nickel nitrate and cobalt nitrate is used as the salt solution in the chemical impregnation method of filling nickel hydroxide.